South African Crustacea. 25 



in front of the recesses for the first antennae. In the male the 

 pleon is bent at the third (the widest) segment, so that the first 

 and second segments occupy a position nearly, if not quite, at 

 right angles with the last three segments. From the second 

 segment nearly to the end "of the pleou "there is a raised central 

 lobe. In the.' female this lobe begins on the first segment, 

 which is the* narrowest, while the fifth is the broadest, the sixth 

 also being very broad, the whole forming a capacious bowl for 

 the ova. 



The male specimen here figured is about 24 mm. long by 

 17 mm. broad. 



Locality. Vasco de Grama S. 75 E., 13^, miles. Depth 

 166 fathoms. No. 248. Sent by Dr. Gilchrist. 



GEN. HYASTENUS, White. 



1847. Hyastenvs, White, Proc. Zool/Soc. London, p.' 56. 

 1913. Caiman, Ann. Nat, Hist., ser. 8, vol. 11, p. 313. 



1916. ' M. J. Rathbun, Proc. U.S. Mus., vol. 50, pp. 



542-548. 



Dr. Caiman explains that it is Pisa aries, Latreille,|which has 

 been referred to Hyastenus,'\not HaJimn.^ arien, Latreille (in 

 Guerin), so that the supposed necessity for making Hyastenits 

 a synonym of Halitnus does not arise. 



HTASTENUS UNCIFER, Caiman. 



1909. Hyastenus uncifer, Caiman, Proc. Zool. Soc. London, pp. 705, 



712, pi. 72, figs. 8, 9. 

 1911. HaUmus uncifer, Mary J. Rathbun, Trans. Linn. Soc. London, 



vol. 14, pt. 2, p. 252, pi.' 20, fig. 7. 



Both authors lay stress on the marginal teeth of the fingers 

 in the ambulatory legs as a distinctive feature. But Dr. de 

 Man in his description of Hyastenus hilgendorfi (J. Linn. Soc. 

 London, vol. 22, p. 18, 1887) says :.." The ,dactylopodites are 

 armed with a row of acute spinules along their inner margins ; 

 these spinules gradually increase in length towards the tip." 

 In the specimen which I am~ referring to Caiman's species 

 these spinules were completely concealed until] the organism was 

 removed, which covered almost the whole of the upper surface 

 of the body and the fingers with a close, felt-like matting. 

 The skin when uncovered had a satiny," dull red appearance. 



The horns measured along the inner margin are 21 mm. long, 

 the interval between the tips is 13 mm., and the length from 



